While most of the LHC experiments are on a grand scale, LHC forward (LHCf) is quite different. Unlike the massive detectors that are used by ATLAS or CMS, LHCf’s largest detector is a mere 30 cm. Rather like the TOTEM detector (see CERN Courier April 1999 p9), this experiment focuses on forward physics at the LHC. The aim of LHCf is to compare data from the LHC with various shower models that are widely used to estimate the primary energy of ultra-high-energy cosmic rays.
The LHCf detectors will be placed on either side of the LHC, 140 m from the ATLAS interaction point. This location will allow the observation of particles at nearly zero degrees to the proton beam direction. The detectors comprise two towers of sampling calorimeters designed by Katsuaki Kasahara from the Shibaura Institute of Technology. Each is made of tungsten plates and plastic scintillators of 3 mm thickness for sampling.
Yasushi Muraki from Nagoya University leads the LHCf collaboration, with 22 members from 10 institutions and four countries. For many of the collaborators this is a reunion, as they had worked on the former Super Proton Synchrotron experiment UA7.